[Android] Hide FAB on scroll

Hide FAB on scroll

(Recyclerview에서 스크롤시 FloatingActionButton 숨기기)

fdRecyclerview.addOnScrollListener(new RecyclerView.OnScrollListener() {
    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        if (dy < 0) {
            fdFab.show();
        }else if (dy > 0) {
            fdFab.hide();
        }
    }
});